Conventional arc lamps, pulsed or continuous, provide a high energy density, high intensity, sharply defined source which is desirable in a number of applications. The high energy density and high intensity make arc lamp sources desirable in spectroscopy where the chemical sensitivity is a direct function of the energy density at the target sample. The high energy density and high intensity are also useful in miniaturization applications such as in fiber optic light transmission for endoscopic uses and generally in photographic illumination applications where a high intensity minute controlled source of illumination is essential. One shortcoming of such lamps is that more than half of the radiation generated is lost because of backscattering of the rearward directed radiation within the arc lamp. Worse still, that lost, backscattered rearward radiation increases the heating of the lamp and contributes to optical noise that interferes with the output beam. In some designs paraboloidal and ellipsoidal internal reflectors have been used to collect and control more of the available arc radiation but because of electrode orientation can cause a void or black hole in the direct radiation, and each of them inadvertently increases magnification at the target which in most applications is undesirable.